Depends on the type of orchids, where you are in the world and the orchid growing conditions you can provide.

The plastic is good because the roots also make photosynthesis and you can be checking them develop. I like the plastic pot.

Didn't know the roots photosynthesize, but I always do better with clay / terracotta. I started collecting orchids several years ago and some are still alive from back then. I switch them to clay as soon as the flowers die (which was 14 months for the most recent orchid I repotted!).

I believe plastic pots are best for beginners to orchids, because the grower can easily check on the root system to see how it's growing. For me, I use plastic pots because like I mentioned above, I like seeing the root system to make sure all is well with the roots.

Like arthurm said, it also depends on your environment. I think a plastic pot would benefit those in a drier environment to keep more moisture inside the media for the roots, while for a more humid environment a clay pot would help dry out the media faster.

I live in a warm, humid environment, South Florida. Terra cotta is what I use. I fill them with lava rock. I can and do water every day. They get wet in the morning and dry by the end of the day. The frequent wet dry cycle imitates the natural cycles of the orchids I grow. If root photosynthesis is needed by the roots they will find their way for exposure. It is not a question of beginner or a seasoned grower. It is what the plant and grower needs. If I had less time I would revert to plastic. That way I could reduce the water frequency. Not optimum but success is achievable.

Clear plastic so I can see the roots. It's the key to me not killing phals too.

For me, it depends on the orchid. Phals - terracotta pots with a bark and sphag mix. Paphs - plastic pots with small bark topped with sphag. Catts/Oncs/Dens - clay or ceramic pot with lots of side holes with bark and coco chips. Vandas/Neos/Asco - hanging basket with coco chips and sphag.

My sunroom is all day direct sun and, despite my best efforts, low humidity. I spray everything on a daily basis and soak once a week or so. Most everything dries out by end of day. So far, it's worked for me.